We are told that domesticated dogs are the direct descendants of the gray wolf, canis lupus, but if that's the case, why do dogs not look like wolves?
Sure, there are several dog breeds that look like wolves such as the Siberian husky, Alaskan malamute, the Samoyed and the German shepherd to just name a few, but many other dog breeds lack the typical "wolfish" appearance one would expect to see in a species that boasts wolves as their ancestors.
Actually, if we look at the more than 300 dog breeds populating the world, we are likely to see more dogs that do not look like wolves than dogs who actually do, so what gives?
Wolf Blood in the Veins
If we look back in time, we notice that dogs were originally classified as ''Canis familiaris '' by Linnaeus in 1758.
However, centuries later, as technology advanced, DNA analysis proved that domestic dogs were not a distinct species, but rather evolved from wolves, canis lupus.
According to Bioweb, a website produced by The University of Wisconsin faculty members, these scientific advances warranted reclassification, therefore, scientists decided to categorize dogs as ''Canis lupus familiaris'' a subspecies of the gray wolf.
Some Striking Similarities
With the grey wolf as an ancestor, all dog breeds from the tiniest Chihuahua to the tallest great dane have wolf in them.
Despite some dogs not looking like wolves, one must consider that wolves and dogs share several similarities.
For instance, wolves and dogs share the same number of chromosomes, exactly 78 arranged in 39 pairs.
This means dogs and wolves can breed and produce viable offspring. According to Furman University, dogs and wolves share 99.8 percent of their genome and the 0.2 percent difference represents the thousands of years of selective breeding that separate the two species.
Yet, Many Differences
Despite being related, wolves and dogs are quite different and that 0.2 percent difference can make quite an impact in both appearance and behavior.
Compared to wolves, dogs have smaller skulls, smaller teeth and weaker jaws. While wolves go in estrus once a year, most dogs go in estrus twice a year and are quite promiscuous.
While all wolves look pretty much the same, dogs come in many different shapes, sizes and colors.
Recent studies have found that a distinguishing factor between wolves and dogs is the ability to digest starch. According to Scientific American, dogs have genes that allow them to digest starch, an adaptation strategy that has likely paved the path to a smoother domestication process considering that humans often fed dogs leftover foods rich in starches.
Many people still believe that "dogs are wolves in sheep's clothing." This assumption of dogs being domesticated wolves, has incited people to look at the behavior of wolves to better understand dogs.
This is a big mistake, for the simple fact that it ignores the many years of domestication that have separated the two species, explains University of British Columbia professor of psychology Stanley Coren in the book "Why Does My Dog Act that Way?"
Looking at wolf behavior to decode dog behavior is like studying a group of chimps to get insights into human behavior, a pretty unacceptable practice as there are too many differences!
A Matter of Genetic Plasticity
The differences between wolves and dogs may have been in great part due to the great “genetic plasticity” tendency of dogs. No other species on earth comes with such extensive genetic variability. Yes, dogs come in all shapes and sizes!
By selectively breeding dogs, humans have been capable of manipulating their characteristics and creating animals with a vast array of characteristics, leading to perhaps one of the largest genetic experiments ever conducted by humans.
A phenomenon that may have contributed to making dogs look different than wolves during their evolution is what's know as "pedomorphosis, " the retention of juvenile traits, also known as neoteny. Intrigued? Discover more about neoteny in dogs.
Humans selectively bred dogs for the retention of juvenile traits because those traits were considered appealing, especially when dogs morphed from working dogs to the role of companions.
Puppies therefore started developing earlier than wolf pups, in a sort of "arrested development" which caused them to look less wolfish and retain infantile characteristics such as floppy ears and snub noses, explain Temple Grandin and Catherine Johnson in the book "Animals Make us Humans."
Dogs Who Look Like Wolves
So what about huskies and malamutes, are they part wolves? They are certainly dog breeds that look like wolves, but according to the International Wolf Center, this is a myth.
Despite looking like wolves, huskies and malamutes are no more wolf than any other breed of dogs.
Same goes with several other dog breeds that have a wolfish appearance. Raymond Coppinger and Lorna seem to agree. They claim that there is no evidence to support that breeds that look like wolves such as German shepherds, are more closely related to wolves.
However, there may be a possible explanation when we compare wolfish looking dogs like the husky with dogs like the Mexican hairless or Afghan hound.
The environment in which huskies were bred was similar to the Northern wolf's habitat, making them more similar to wolves than a dog being bred over the years to live in a warm or desert-like habitat.
Yet, wolves and many wolfish looking dogs breeds are still a far cry from each other. There are a few exceptions to the rule though, and these are mostly dogs who were developed recently by using wolf stock.
Recent Wolf Blood
While dogs and wolves are quite different looking, there are some dogs that actually have wolf blood recently added, with the end result that they look more like wolves than the average dog.
Wolf hybrids are dogs who do indeed have wolf in them as they're crossed with wolves, but the ‘amount of wolf blood’ tends to vary greatly with some hybrids yielding predominantly dog or predominantly wolf traits, or any combination in between.
Caroline Coile and Margaret Bonham though explains that wolf hybrids do not make up a breed. However, there are some unusual dog breeds who actually have recent wolf blood in them and these include the Czechoslovakian Wolfdog and the Saarloos Wolfhound.
Did you know? According to a study conducted by John W. Fondon III and Harold R. Gardner, the great genetic variability in dogs may be attributed to gene-associated tandem repeat expansions and contractions. These are basically short lengths of DNA that are repeated multiple times within a gene.